Feasibility of a Polymer Foaming Agent as a Grouting Material for Broken Coal Masses

Table 4

Uniaxial compressive test results of different grouting reinforced specimens.

Grouting material	Specimen	D (mm)	H (mm)	(MPa)	(MPa)	Strength recovery coefficient
SC	SC-1	49.8	100.1	7.26	6.16	0.52
	SC-2	49.4	99.7	5.99
	SC-3	49.7	99.9	6.31
	SC-4	49.5	100.2	5.09
PF	PF-1	49.6	100.1	12.01	10.85	0.91
	PF-2	49.5	100.2	10.99
	PF-3	49.3	99.8	9.80
	PF-4	49.7	100.1	10.58

Note: strength recovery coefficient is the ratio of the concretion’s uniaxial compressive strength to the raw coal’s uniaxial compressive strength.